Have the oceans always been salty?

Have you ever wondered why beach water is salty while lake water is not? Ever thought about how this salt ended up within the sea? If yes, then let’s see what the story behind it is.

The world that we live and breathe in was not always like this. When the earth was still young and in its early days, it was surrounded by an atmosphere of nasty gases. It was composed of a mixture of a toxic compound, hydrogen bromide, and other noxious emissions from volcanoes. These caused a bitter environment on our planet. And since two-third parts of the earth are water, these gases affected it too.

Oceanographers believe that some of these gases dissolved in the primitive ocean, making it salty. Therefore, you can say that the bitterness of the oceans is not new. In fact, it has always been around.

The process mentioned above suggests that the root of the saltiness of oceans are toxic gases. But there is something else that we should learn about this phenomenon. According to this theory, water can absorb different gases that can later change its properties and taste. So, one can assume that if those gases were absorbed by the seawater, can our chemical waste and other things also have an impact on the ocean? Technically, yes. But we cannot compare the toxicity of those gases to our everyday waste. Then again, we can also not entirely cross this out as it makes a change even if it is not noticeable right now.

Even though we cannot say for sure that waste is causing saltiness, there is another theory of this process, which is quite relatable to us. It suggests that most of the salt in the oceans comes from the regular rinsing of the earth. You see, when rain falls down on land, it dissolves the salts in eroding rocks. These salts, in turn, mix with the water that is carried down the rivers, and finally out to the seas.

When this copious amount of salt is dissolved in the water, it becomes salty, but not salty enough. Later, it is subjected to the process of evaporation. As a result of which, it accumulates in the ocean as water evaporates to form clouds. This is how oceans are getting saltier every day, but the rate of this increment is so slow that it is virtually immeasurable.

One more thing that should be considered while discussing the salt level in the seawater is the quantity of salts, which varies from ocean to ocean. Even if you compare different parts of one ocean, you will still find great variation—the mineral content changes, depending on the depth and environment. For example, there is about 3 percent salt in the water of the North Sea and the Atlantic. Similarly, there is up to 4 percent salt content in the Mediterranean. At the other end of the scale, the Baltic has about 1% to 2% salt ratio. Lastly, the Dead Sea contains about 25 to 27 percent of salts.

There is so much salt and minerals dissolved inside our oceans, we cannot even imagine. Theoretically speaking, if by chance, the oceans dry up, enough salt will be left behind to build 290 kilometers tall, 1.5 kilometers thick wall around the equator. Isn’t this mind-blowing?

Moreover, almost 90% of sea salt is sodium chloride or ordinary table salt. And if you want, you can collect it for your daily use. Just get some water from the beach, strain it, and then keep it under the sun. After a while, all the water will vaporize, and you will be left with fresh table salt that can be used for cooking purposes.

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